Merge pull request 'Guarder protected with semaphor' (#1) from semaphor-protection into main

Reviewed-on: #1

src/guarder.h

@@ -4,26 +4,37 @@
 #include <sys/types.h>
 #include <sys/shm.h>
 #include <sys/ipc.h>
+#include <sys/sem.h>
+#include <unistd.h>
 
 class guarder{
 private:
     const int shmid;
+    const int semid;
+
+    void semaphoreOp(int op) {
+        struct sembuf sb{};
+        sb.sem_num = 0;
+        sb.sem_op = op;
+        sb.sem_flg = 0;
+        semop(semid, &sb, 1);
+    }
 
     void setFlag(bool value)
     {
+        semaphoreOp(-1);
         bool *flag = static_cast<bool *>(shmat(shmid, nullptr, 0));
         *flag = value;
         shmdt(flag);
+        semaphoreOp(1);
     }
 
 public:
-    guarder() : shmid(shmget(IPC_PRIVATE, sizeof(bool), 0666 | IPC_CREAT))
+    guarder() : shmid(shmget(IPC_PRIVATE, sizeof(bool), 0666 | IPC_CREAT)), semid(semget(IPC_PRIVATE, 1, 0666 | IPC_CREAT))
     {
         setFlagOff();
     }
 
-    guarder(guarder &g) : shmid(g.shmid) {}
-
     void setFlagOff()
     {
         setFlag(false);
@@ -36,15 +47,18 @@ public:
 
     bool isFlagOn()
     {
+        semaphoreOp(-1);
         bool *flag = static_cast<bool *>(shmat(shmid, nullptr, 0));
         bool ret = *flag;
         shmdt(flag);
+        semaphoreOp(1);
         return ret;
     }
 
     ~guarder()
     {
         shmctl(shmid, IPC_RMID, nullptr);
+        semctl(semid, 0, IPC_RMID);
     }
 
 };

src/main.cpp

@@ -10,7 +10,6 @@
 #include "locations.h"
 #include "usermanager.h"
 #include "guarder.h"
-#include "processManager.h"
 
 #define MAXNAMESIZE 255
 #define SCAN_DONE_SIG SIGRTMIN
@@ -87,7 +86,6 @@ int main()
 
         int size;
         char *buffer = nullptr;
-        processManager pm;
 
         while (read(p1[0], &size, sizeof(int)))
         {
@@ -96,11 +94,12 @@ int main()
 
             read(p1[0], buffer, size * sizeof(char));
             std::string name(buffer);
-            std::string cmd = std::string(SCAN_CMD_USR) + name;
 
             std::cout << "Scan received for: " << name << std::endl;
 
-            pm.runTask(name, cmd);
+            guard.setFlagOn();
+            system((std::string(SCAN_CMD_USR) + name).data());
+            guard.setFlagOff();
 
             kill(parent, SCAN_DONE_SIG);
 

src/processManager.h

@@ -1,41 +0,0 @@
-#ifndef _PROCCESSMANAGER_H
-#define _PROCCESSMANAGER_H
-
-#include <map>
-#include <string>
-#include <unistd.h>
-#include <sys/types.h>
-#include "guarder.h"
-#include "usermanager.h"
-
-class processManager
-{
-private:
-    std::map<std::string, guarder> running;
-
-    bool getIdTag(std::string &id)
-    {
-        return running[id].isFlagOn();
-    }
-
-
-public:  
-
-    void runTask(std::string &id, std::string &cmdCommand)
-    {
-        if (!getIdTag(id))
-        {
-            running[id].setFlagOn();
-            pid_t child = fork();
-
-            if (child == 0) // child
-            {
-                system(cmdCommand.c_str());
-                running[id].setFlagOff();
-                exit(EXIT_SUCCESS);
-            }
-        }
-    }
-};
-
-#endif // _PROCCESSMANAGER_H